1. Field of the Invention
This invention relates to a room temperature curable resin composition, and more particularly to a room temperature curable resin composition that can be cured at an accelerated rate not only at the surface but also at the depths thereof, and give a cured product with a superior toughness.
2. Description of the Prior Art
Hitherto known as room temperature curable resins are thermoplastic resin compositions mainly comprised of a polymer having a hydrolyzable silyl group in its molecule. Known as this polymer having a hydrolyzable silyl group in its molecule are a copolymer of a monomer having an unsaturated group with an alkoxysilane having a vinyl functional group or acrylic functional group, a product obtained by grafting the above alkoxysilane onto a thermoplastic polymer (Japanese Patent Publication (KOKOKU) No. 1711/1973, etc.).
The above alkoxysilane having a vinyl functional group includes vinylsilane such as vinyltrimethoxysilane and a silane having a vinyl ether group, such as gammavinyloxypropyltrimethoxysilane. These, however, are too poor in the copolymerizability to be suitable as materials for synthesizing polymers having hydrolyzable silyl group.
On the other hand, the alkoxysilane having an acrylic functional group, as exemplified by gammamethacryloxypropyltrimethoxysilane, have a high copolymerizability but are disadvantageous in that, when the resin compositions mainly comprised of the resulting polymer are cured, they can only be cured at a log rate at the depths of the composition to be cured, and that the resulting cure product is so brittle that. It may be liable to crack.